Tesla may be in serious trouble. At least, that's the opinion of Moody's analyst Bruce Clark, who had just downgraded the company's credit rating from B3 to B2, and its outlook from "stable" to "negative." And, Clark told CNBC, this is a critical time for Tesla.

Why does he think so? To begin with, Tesla needs quite a lot of cash to fund its day-to-day operations, about half a billion dollars a year, according to Moody's calculations. It will have to spend another $2 billion in 2018 to ramp up Model 3 production. And it will need to pay off $1.2 billion in debt by early next year. Tesla does have some cash and securities, and a line of credit that's not entirely used up. But these won't be enough to cover Tesla's needs, so the company will need to raise a lot more capital--more than $2 billion, Moody's analysis says--probably by selling bonds.

That's where Model 3 production comes in. Tesla has a history of missing its own projections about production and the Model 3 is fitting in with that tradition so far. Back in July when the first non-Tesla-employee Model 3s were handed to their owners, Tesla founder Elon Musk tweeted, "Looks like we can reach 20,000 Model 3 cars per month in Dec."

Not so much. At the end of last year, Tesla reported it had made only 1,550 Model 3s in the whole fourth quarter, just a bit more than half the number analysts were hoping for. It had projected making 5,000 cars a week through 2017, rising to 10,000 a week by the end of 2018. 

It has since reduced its projections to 2,500 Model 3s a week at the end of March and 5,000 a week by the end of June. If it can hit these new targets, Moody's says, Tesla will be able to raise the capital it needs at reasonable interest rates. If it misses them, it won't, and things could get very awkward.

The markets have reacted brutally to these cash worries--and a National Traffic Safety Board investigation of a fatal crash involving a Tesla in autopilot mode didn't help. Tesla's share price has tumbled from its one-time high of $389.61 to $257.78 when the market closed Wednesday. John Thompson, a hedge fund manager who's been betting against Tesla for years, gleefully predicted that the company is now months away from bankruptcy.  

That seems more than a bit premature. As Moody's noted, with or without profits at this time, the company has a lot going for it. It has captured more than a third of the U.S. luxury car market, a remarkable achievement for an electric car company. And macro trends are in its favor. A growing list of countries have announced that they will ban the sale of new gasoline-powered cars in the coming decades, while the federal government continues (at least for the moment) to offer subsidies for new electric car purchases. Rising oil prices might help too.

It seems it will all come down to how many Model 3s Tesla managed to make in March. We could get the answer to that question as soon as Monday. Stay tuned.